Interstitial concentrations of adipokines in subcutaneous abdominal and femoral adipose tissue

Abstract

Adipokines play important regulatory roles in the pathophysiology of obesity and insulin resistance. We measured plasma and interstitial concentrations of the adipokines adiponectin, resistin, leptin, monocyte chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6) and interleukin-8 (IL-8) in subcutaneous, abdominal and femoral adipose tissue using calibrated, large-pore microdialysis technique in 8 healthy, lean men on 2 experimental days. The interstitial leptin concentration was 2.5-fold higher in subcutaneous, femoral than abdominal adipose tissue ( P < 0.05), but no regional differences were found for the remaining adipokines ( P > 0.05). Adiponectin and leptin concentrations were higher in plasma than subcutaneous adipose tissue (∼ 25-fold and ∼ 2-fold, respectively, P < 0.05), whereas MCP-1, IL-6 and IL-8 concentrations were higher in subcutaneous adipose tissue than plasma (∼ 100-fold, ∼ 200-fold and ∼ 1000-fold, respectively, P < 0.05). Resistin concentrations did not differ significantly between compartments. Adipose tissue blood flow (ATBF) showed no regional difference ( P > 0.05). The intra- and inter-subject variations of all investigated adipokines as well as of ATBF were substantial (coefficient of variation: 4–177%). In conclusion, interstitial leptin concentrations are ~ 2.5-fold higher in subcutaneous, femoral than abdominal adipose tissue, which might be a potential mechanism behind the health-benefits of “pear-shape”. Furthermore, subcutaneous adipose tissue has a marked production of pro-inflammatory adipokines.